1. Field
One or more aspects of example embodiments of the present disclosure relate to a color substrate including a retroreflective layer and a display device including the color substrate.
2. Description of the Related Art
A liquid crystal display device is a widely used display device and includes a liquid crystal layer including liquid crystal molecules configured to assume different orientations according to an applied electric field (e.g., voltage). The liquid crystal display device may be configured to display an image by controlling the polarization of incident light through the liquid crystal layer.
The liquid crystal display device includes red, blue, and green color filters to form light of specific colors. However, when white light emitted by a backlight source passes through a red color filter, a green color filter, and/or a blue color filter, the light intensity is reduced by about ⅓ at each of the red, green, and blue color filters, thereby reducing the light efficiency of the device.
A photo-luminescent liquid crystal display (PL-LCD) apparatus has been suggested to overcome the low light efficiency of LCD displays and to increase or improve color reproducibility. The PL-LCD apparatus includes a quantum dot-color conversion layer (QD-CCL) instead of the color filters used in a general LCD apparatus. The PL-LCD apparatus displays a color image when short wavelength light, such as ultraviolet (UV) light or blue light generated from a light source, is irradiated onto a color conversion layer (CCL) to thereby generate visible light of different colors that is subsequently controlled by a liquid crystal layer.
Since the CCL generates light having a different wavelength from light emitted by the light source, as opposed to transmitting the light source through a color filter, light emitted by the CCL is irradiated in various directions. Furthermore, a portion of the light emitted by the light source may be transmitted without being converted in a CCL. Accordingly, adjacent first and second color lights emitted by adjacent CCLs and/or a third color light emitted by the light source may mix, thereby changing the apparent colors of each. Color reproducibility may be reduced due to this color mixing.
A black matrix may be positioned between pixel regions to prevent or reduce color mixing. When the black matrix is formed of a reflective material, light emitted by each CCL may be reflected by the black matrix and irradiated onto an adjacent CCL. In this case, color mixing may increase. When the black matrix is formed of a light-absorbing material, the light efficiency may be reduced when light emitted by the CCLs is absorbed by the black matrix.